How can we avoid overlook cancer in FDG-PET?

I classify a factor to lead to a fall of diagnosis ability roughly into imaging factor and reading factor. Imaging factor means how to keep imaging quality and to reduce artifact. An optimum condition may vary in every institution, but excessive shortening of acquisition time should be avoided. A respiratory gated method to reduce motion artifact from diaphragm is introduced in this article. As for reading factor, most important way to avoid misreading is to compare PET image with CT/MRI. PET-CT may be strong tool to avoid overlook abnormal finding by merging anatomical and functional imaging.